diff --git a/install-dev/upgrade/sql/1.5.6.1.sql b/install-dev/upgrade/sql/1.5.6.1.sql
index 435bb1009..92c3a8d12 100644
--- a/install-dev/upgrade/sql/1.5.6.1.sql
+++ b/install-dev/upgrade/sql/1.5.6.1.sql
@@ -1 +1,3 @@
-ALTER TABLE `PREFIX_customer_message` CHANGE `ip_address` `ip_address` VARCHAR( 15 ) NULL DEFAULT NULL;
\ No newline at end of file
+ALTER TABLE `PREFIX_customer_message` CHANGE `ip_address` `ip_address` VARCHAR( 15 ) NULL DEFAULT NULL;
+
+UPDATE `PREFIX_orders` SET conversion_rate = 1 WHERE conversion_rate = 0;